Alessandro Campaiola is an Italian voice actor born in Rome on November 19, 1992. He comes from a prominent family in the Italian dubbing industry; his mother is voice actress Monica Ward, his uncles are Luca Ward and Andrea Ward, and his younger brother, Federico Campaiola, is also a voice actor. Campaiola's great-grandmother was a theater actress who provided the voice for the witch in the first Italian dubbing of Disney's Snow White and the Seven Dwarfs. He performed his first voice role at the age of four but decided to pursue the career seriously at fifteen.

In the realm of animation and anime, Campaiola is known for several prominent roles in the Italian adaptations. He voices Adam Bindewald in the animated Godzilla film trilogy: Godzilla: Planet of the Monsters, Godzilla: City on the Edge of Battle, and Godzilla: The Planet Eater. He also provides the voice for Hikaru Hoshihara in the series Danbōru Senki Wars. Beyond these, his notable anime roles include Eren Jaeger in Attack on Titan and Saitama in One-Punch Man. His other voice work in animation includes Trent in Total Drama Island, Jadeite in Pretty Guardian Sailor Moon Crystal, Ruth in The Ancient Magus' Bride, Crash Bandicoot in Skylanders Academy, and Don in The Promised Neverland.

In addition to his anime roles, Campaiola has an extensive career dubbing live-action films and television series. He is the regular Italian voice for actors such as Taron Egerton, Evan Peters, Harry Styles, and Anthony Ramos. He is particularly well-known for dubbing Barry Allen / Flash, played by Grant Gustin, in the television series The Flash and for voicing Steve Harrington in Stranger Things.

Campaiola is also a theater actor and is a member of the theater company I FuoriSync. In 2021, he was awarded Best Italian Voice Actor. He has been involved in initiatives related to his profession, such as launching a petition alongside his brother to advocate for the Italian dubbing of the final part of Attack on Titan, which gathered thousands of signatures.